Air conditioning unit



April 29, 1969 D A, FRAGNlTO ET AL 3,441,082

AIR CONDITIONING UNIT Filed April 25, 1967 FIG. 5

@v1/MVM AM 43 INVENTORS` DANIEL A. FRAGNITO.

RL C. HERB.

ATTORNEY.

United States Patent O U.S. Cl. 165-123 2 Claims ABSTRACT F THEDISCLOSURE A room terminal for use in an air conditioning system. Air isprovided to the units `from a central station, the discharge of air fromthe units being regulated by a sliding plate damper.

Background of the invention This invention relates to air conditioningsystems employing a central station air conditioner to provideconditioned air for supply through connecting ductwork to a plurality ofunits located in the areas to be conditioned. The type of room unitemployed with the central air conditioner is dependent on the buildingdesign, type of activities carried on in the building, the climate andmany other conditions.

Thus a room unit relying solely on the air from the central station forheating, cooling, humidifying the area might be utilized.

Another type of room unit is one in which the air from the centralstation is blown through a reheat coil which is thermostaticallycontrolled to temper the air and maintain the desired air temperature inthe area irrespective of cooling or heating load variations. In thisWay, the temperature in each area served by the central station may bevaried to suit the occupants of the area.

Still another type of room vunit is one in which a thermostaticallycontrolled heat exchanger, through which a heat transfer uid flows, isprovided in the room unit, the air from the central station, referred toas primary air, being discharged in the unit in such a manner as toinduce room air, referred to as secondary air, through the heatexchanger where it mixes with the primary air and is discharged backinto the area being conditioned.

When any of the foregoing types of room units are installed, it isdesirable to balance the system, that is, regulate the amount of airflow through each unit to match the requirements of the area beingconditioned.

A damper is usually provided in each room unit for this purpose. One ofthe problems that is encountered with dampers in room units is thechange of direction of the air stream leaving the damper as the damperadjustment is varied. For the room unit to operate at maximum eciencyand minimum noise levels, the direction of air ow from the damper shouldnot change with variations in damper adjustments.

Summary of the invention In accordance with a preferred embodiment ofthis invention, an air conditioning system is provided with room unitsemploying a sliding plate damper for regulation of air ow therethrough.The damper, in accordance with this invention comprises two perforatedparallel plates having one plate superposed on the other withsubstantially aligned offsets formed therein rso that the walls of theperforations forming air passages therebetween lie in the same plane.

Brief description of the drawings FIGURE 1 is a View, partlydiagrammatic and partly in perspective, illustrating the airconditioning system of the present invention;

3,441,082 PatentedApr. 29, 1969 FIGURE 2 is a sectional view of a roomunit employed with the system shown in FIGURE l;

FIGURE 3 is a fragmentary sectional view of the sliding plate damper foruse in a room unit illustrating the prior art;

FIGURE 4 is a fragmentary sectional view of the slidin g plate damper ofour invention taken along lines IV-IV of FIGURE 2; and

FIGURE 5 is a fragmentary plan view of the damper illustrated in FIGURE4.

Description of the preferred embodiment The air conditioning systemillustrated in FIGURE l comprises suitable air conditioning apparatusplaced in a central location 2, such apparatus being contained in acasing 3. The apparatus may be disposed in any suitable place in thebasement, on the roof or in a storage space of a building servedthereby. A fan 4 is provided to draw air through the casing 3, the airbeing conditioned in any desired manner during its passage throughcasing 3, and then to discharge the conditioned air at relatively highstatic pressure and high velocity into an air conduit such as riser 5.

The air conditioning apparatus illustrated at 2 may be of any desiredtype and it is understood that the present invention is not limited withrespect to the apparatus illustrated. As illustrated, apparatus 2includes a plurality of dampers `6 through which air is drawn intocasing 3 from the exterior of the building, a filter 7, a preheatingcoil 8 through which heat exchange medium such as steam may be passed topreheat the air drawn into easing 3, sprays 9, a dehumidication orcooling coil 10 and a reheating coil 11. In such apparatus, air issuitably conditioned in accordance with the requirements of the areas tobe conditioned.

Conditioned air is forced through riser 5 by fan 4 and through a run-out12 to room conditioning units 13 placed in one or more bays of thebuilding structure being conditioned. It will be appreciated partitionsmay separate the bay into a plurality of individual areas to beconditioned or the entire bay may be treated as a single area to beconditioned.

Heat exchange medium such as hot water is supplied to the heat exchangemembers 15 of the room units 13. A pump 17 is provided for pumping waterfrom heater 19 through line 21 to the unit heat exchange members andback to heater 19 through line 23.

The room unit 13 includes a casing 25 having a sliding plate damper 27,heat exchanger 15 and discharge grille 29 disposed therein. The slidingplate damper in conjunction with the bottom portion of casing 25 forms aplenum 31 which is supplied with conditioned air from air conditioningapparatus 2 through run-out 12. Thus air is discharged from plenum 31through damper 27, heat exchanger 15 and discharge grille 29 into thearea to be conditioned. The sliding plate damper 27 is of novelconstruction, as illustrated in FIGURES 4 and 5. It is to be understoodthat an operating mechanism, not shown, is provided for sliding theplates relative to each other. In ordinary sliding plate dampers, asillustrated in FIGURE 3, when the damper is wide open, air is dischargednormal to the plane of the plates. However, as the damper is adjusted torestrict flow therethrough, the air stream is deflected, as illustratedby the arrows in FIGURE 3. Heretofore, the use of a sliding plate damperhas resulted in less than optimum unit efliciency and high noise levelsas the direction of air flow therethrough varied with the damperadjustment.

The sliding plate damper of our invention comprises bottom plate 40having a plurality of openings 42 therethrough having opposed end walls43 and 44. A top plate 48 in mating engagement with bottom plate 40 hasa plurality of openings 49 therethrough having opposed end walls 50 andS1, one edge of each opening in plate 48 having an offset portion 54formed therein, each portion 54 being offset one plate thickness so asto be in substantially the same horizontal plane of plate 40. The walls50 on offset portions 54 are thereby in alignment with mating walls 44on plate 40.

By utilizing the damper of our invention, the direction f air flowthrough the unit is not changed by adjustment of the damper, allowing aunit construction having lower noise levels and greater efficiency.

The damper of our invention has been described in relation to a roomunit utilizing a reheat coil. It is Within the scope of the invention toutilize a damper with a wide variety of room units, such as an all airunit, an induction type unit, wherein the air provided from the centralstation (primary air) would be discharged in the unit in a manner toinduce room air (secondary air) through the unit over a heat exchangerand then back into the room.

Further, while we have described a sliding plate damper having offsetportions on one plate lying in the plane of the second plate, it is tobe understood that each plate could have offset portions extendingone-half a plate thickness into the mating plate, thus providing alignededges in a plane between the two plates.

We claim:

1. A room terminal for use with an air conditioning system comprising ahousing,

a plenum disposed in said housing for receiving conditioned air,

a discharge grille disposed in said housing for passing conditioned airfrom the room terminal into the area being conditioned,

a first, relatively tlat plate, disposed in said housing between saidplenum and said discharge grille having at least one opening disposedtherein, said opening being formed by removing material from the plateto form an opening having opposed side Walls and opposed end walls,

a second relatively flat plate having at least one opening disposedtherein, said opening being formed by removing material from the plateto form an opening having opposed side walls and opposed end walls, saidsecond plate overlying said first plate and being arranged so that thelower surface of said second plate slidably engages the upper surface ofsaid first plate,

at least one of said plates having a portion adjacent to and includingone wall deformed from the plane of the plate so the deformed wallresides substantially planar with and opposite said wall in the otherplate to form an opening therebetween for restricting the air flowtherethrough by relative movement of said plates.

2. A room terminal according to claim 1 further including a heatexchange coil disposed in the room terminal in heat exchange relationwith the air flowing through the terminal.

References Cited UNITED STATES PATENTS 2,463,322 3/1949 Sewell et al.165-l23 X 3,211,218 10/1965 Mehr et al. 165-123 FOREIGN PATENTS 350,788l/ 1961 Switzerland.

MEYER PERLIN, Prima/y Examiner.

THEOPHIL W. STREULE, Assistant Examiner.

U.S. Cl. X.R. 98-40

